DISEASE CHARACTERISTICS:

• Morphologically proven acute lymphoblastic leukemia (ALL)

  • Subtypes L1, L2, or L3
  • Bone marrow morphology with greater than 25% lymphoblasts
  • ALL morphology and cytochemistry with myeloid markers eligible

• Refractory to induction therapy or relapsed following chemotherapy or autologous blood or bone marrow transplantation

  • Any number of prior relapses allowed
  • No relapse following allogeneic transplantation
• Prior CNS leukemia allowed if treated and currently disease-free

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• ECOG 0-2

Life expectancy:

• At least 6 months

Hematopoietic:

• Not specified

Hepatic:

• Bilirubin no greater than 2.0 mg/dL
• SGOT/SGPT no greater than 2 times upper limit of normal (ULN)
• Alkaline phosphatase no greater than 2 times ULN

Renal:

• Creatinine no greater than 2 mg/dL

Other:

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No significant active infection
• No other medical conditions that would likely decrease life expectancy
• No other prior malignancy within the past 5 years except cured basal or squamous cell skin cancer or carcinoma in situ of the cervix

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• See Disease Characteristics

Chemotherapy:

• See Disease Characteristics

Endocrine therapy:

• At least 2 weeks since prior systemic corticosteroids

Radiotherapy:

• Not specified

Surgery:

• Not specified

Other:

• No concurrent antibiotics for active or resolving infection